MRI: Acquisition of equipment for an integrated gas analysis and labeling radiocarbon system with a focus on Arctic carbon and geochronology

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This award supports the acquisition of a radiocarbon system at Northern Arizona University. This system will be used to study modern changes in the carbon cycle and past changes in climate. Radiocarbon (Carbon-14 or 14C) is an isotope of carbon, with six protons and electrons, with two additional neutrons. Radiocarbon acts as a clock due to the constant radioactive decay that occurs as a result of the extra neutrons. Radiocarbon dating is the most widely used scientific tool for determining the timing of events and the rates of changes of Earth, environment and human processes extending back tens of thousands of years. This grant supports purchase of instruments to complete a gas and labeling radiocarbon system that will allow the investigators to gain novel insights into environmental issues in the Arctic. These instruments will be integrated with educational activities that promote training scientists in the application of radiocarbon to ecology and Earth system science.Recognizing the outstanding potential for transformative research, Northern Arizona University (NAU) recently contracted IonPlus for the purchase of a mini accelerator mass spectrometer (Mini Carbon Dating System; MICADAS). This award funds the acquisition of a gas and labeling radiocarbon system including a gas ion source (GIS), which is needed for rapid analysis of very small samples in CO2 gas form, and automated graphite equipment (AGE), which combines sample combustion, purification, and graphitization steps and will be used to isolate samples from low-level labeling experiments and complete an integrated analytical facility. The proposed instrumentation will link novel and developmental applications of radiocarbon to grand challenges in Earth and environmental sciences, with a particular focus on the Arctic. Radiocarbon provides a unique and sensitive fingerprint for tracking changes in the permafrost carbon pool, for understanding feedbacks in the Arctic climate system, and for understanding past climate change. Technological breakthroughs for measuring radiocarbon and the scientific expertise at NAU together are poised to catalyze novel insight into these issues. The NAU PIs, along with a broad suite of collaborators, will explore two major themes of understanding (1) past changes in Arctic climate, and (2) modern changes in Arctic carbon that may feedback to future climate. In addition to this Arctic-focused theme, the instrumentation will facilitate ongoing research across a broad range of sciences including soil carbon dynamics, plant and microbial ecology, fire history, geologic hazards, archaeology, historical ecology and conservation paleobiology. This instrument acquisition will be integrated with educational and knowledge transfer activities that promote training scientists in the application of radiocarbon to ecology and Earth system science. Technological advances such as represented by the integrated radiocarbon system in this grant could help spread the use of radiocarbon, with increases in the variety of applications and in options for preparing samples, and decreases in cost. This requires an expanding pool of educated users, which will be generated by a short course, Radiocarbon in Ecology and Earth System Science, open to graduate students and postdoctoral researchers nationwide. In addition, NAU has a strong commitment to serving rural Arizona, including Native American and Hispanic populations. Existing programs will be leveraged to engage these students, providing lab tours, demonstrations, and opportunities to work in the lab.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.